Vitamin E Attenuates FasL-Induced Apoptotic Death of Dendritic Cells Through PI3K Signalling

Vitamin E (VitE) is a potent antioxidant and contributes as an apoptosis inhibitor by preventing apoptotic death by suppressing cell membrane scrambling with phosphatidylserine translocation and caspase activites. Fas ligand (FasL) is well known to induce cell apoptosis. Activation of phosphoinositide 3 kinase (PI3K) signalling is stimulated by VitE. The present study addressed the effects of VitE on survival of mouse dendritic cells (DCs) and signalling molecules underlying. To this end, mouse bone marrow cells were isolated and cultured to attain bone marrow-derived DCs (BMDCs). The cells were treated with FasL in the presence or absence of VitE. Western blotting and FACS analysis were performed to determine expression of signalling molecules and their involvement in DC apoptosis. As a result, FasL treatment resulted in activation of caspase 8 and an increased number of Annexin V+ cells, the effects were significantly suppressed when VitE was present in the cell culture. 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